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Results found in several dictionaries: Collins, Collaborative Dictionary
cigarette butt 
  n mégot  m 

Collaborative Dictionary     English-French
cigarette smoking n. le tabagisme Reverso General Dictionary 
automatic cigarette vending machine n. le distributeur automatique de cigarettes Reverso General Dictionary 
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'cigarette butt' also found in translations in French-English dictionary
crosse n. 1) butt (f), 2) stick (f) Reverso General Dictionary 
! taxer nnpl. var pop : demander une cigarette à qqn " je peux... 
pantalon cigarette pref. cigarette pants Reverso General Dictionary 
fume-cigarette pref. cigarette holder Reverso General Dictionary 
contrebande de cigarettes nm. cigarette smuggling Reverso General Dictionary 

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